h1 {
    font-size: 20pt;
    font-family: sans-serif;
    font-weight: bold;
    color: black;
    text-align: center;
}

#Interface {
    width: 400px;
    height: 690px;
    border: 4px solid black;
    margin-left: auto;
    margin-right: auto;
}

#Display {
    display: block;
    width: 400px;
    height: 186px;
    border: 1px solid black;
    background-color: black;
    color: white;
    font-size: 40pt;
    text-align: right;
}

#Keyboard {
    width: 400px;
    height: 400px;
    margin: 0;
    position: absolute;
}

button {
    width: 100px;
    height: 100px;
    border: 1px solid black;
    position: absolute;
    font-size: 20pt;
    background-color: lightgray;
    outline: none;
}

.operator {
    background-color: orange;
    color: white;
}
.other {
    background-color: darkgray;
}

.CE {
    left: 0;
    top: 0;
}
.Lbracket {
    left: 100px;
    top: 0;
}
.Rbracket {
    left: 200px;
    top: 0;
}
.divide {
    left: 300px;
    top: 0;
}
.seven {
    left: 0;
    top: 100px;
}
.eight {
    left: 100px;
    top: 100px;
}
.nine {
    left: 200px;
    top: 100px;
}
.multiply {
    left: 300px;
    top: 100px;
}
.four {
    left: 0;
    top: 200px;
}
.five {
    left: 100px;
    top: 200px;
}
.six {
    left: 200px;
    top: 200px;
}
.minus {
    left: 300px;
    top:200px;
}
.one {
    left: 0;
    top: 300px;
}
.two {
    left: 100px;
    top: 300px;
}
.three {
    left: 200px;
    top: 300px;
}
.plus {
    left: 300px;
    top: 300px;
}
.dot {
    left: 0;
    top: 400px;
    color: black;
    background-color: lightgray;
}
.zero {
    left: 100px;
    top: 400px;
}
.delete {
    left: 200px;
    top: 400px;
    background-color: lightgray;
}
.equal {
    left: 300px;
    top: 400px;
}

#Positioner {
    position: fixed;
    right: 10px;
    display: block;
    width: 200px;
    height: auto;
    border: 2pt solid black;
}

#Button {
    display: block;
    position: absolute;
    right: 10px;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background-color: deepskyblue;
}